If you are considering a job sharing arrangement, you and the other person should apply together for the job. If you decide later in the process to share one position (referred to as one full-time equivalent or FTE), there are several legal hurdles (Affirmative Action, nepotism rules) to navigate. In the negotiation process, make sure your salary is at the upper end of the salary spectrum; insist on separate offices, separate travel funds, and separate (double) pension benefits. Merit reviews and tenure reviews are usually separate. It is wise to put stipulations in your contract regulating the dissolution of the arrangement in case of divorce or separation or the failure of one partner to achieve tenure.